// MIT License

// Copyright (c) 2019 Erin Catto

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include "test.h"
#include "imgui/imgui.h"

class EdgeTest : public Test
{
public:

  EdgeTest()
  {
    b2Vec2 vertices[10] =
    {
      {10.0f, -4.0f},
      {10.0f, 0.0f},
      {6.0f, 0.0f},
      {4.0f, 2.0f},
      {2.0f, 0.0f},
      {-2.0f, 0.0f},
      {-6.0f, 0.0f},
      {-8.0f, -3.0f},
      {-10.0f, 0.0f},
      {-10.0f, -4.0f}
    };

    m_offset1.Set(0.0f, 8.0f);
    m_offset2.Set(0.0f, 16.0f);

    {
      b2Vec2 v1 = vertices[0] + m_offset1;
      b2Vec2 v2 = vertices[1] + m_offset1;
      b2Vec2 v3 = vertices[2] + m_offset1;
      b2Vec2 v4 = vertices[3] + m_offset1;
      b2Vec2 v5 = vertices[4] + m_offset1;
      b2Vec2 v6 = vertices[5] + m_offset1;
      b2Vec2 v7 = vertices[6] + m_offset1;
      b2Vec2 v8 = vertices[7] + m_offset1;
      b2Vec2 v9 = vertices[8] + m_offset1;
      b2Vec2 v10 = vertices[9] + m_offset1;

      b2BodyDef bd;
      b2Body* ground = m_world->CreateBody(&bd);

      b2EdgeShape shape;

      shape.SetOneSided(v10, v1, v2, v3);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v1, v2, v3, v4);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v2, v3, v4, v5);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v3, v4, v5, v6);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v4, v5, v6, v7);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v5, v6, v7, v8);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v6, v7, v8, v9);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v7, v8, v9, v10);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v8, v9, v10, v1);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetOneSided(v9, v10, v1, v2);
      ground->CreateFixture(&shape, 0.0f);
    }

    {
      b2Vec2 v1 = vertices[0] + m_offset2;
      b2Vec2 v2 = vertices[1] + m_offset2;
      b2Vec2 v3 = vertices[2] + m_offset2;
      b2Vec2 v4 = vertices[3] + m_offset2;
      b2Vec2 v5 = vertices[4] + m_offset2;
      b2Vec2 v6 = vertices[5] + m_offset2;
      b2Vec2 v7 = vertices[6] + m_offset2;
      b2Vec2 v8 = vertices[7] + m_offset2;
      b2Vec2 v9 = vertices[8] + m_offset2;
      b2Vec2 v10 = vertices[9] + m_offset2;

      b2BodyDef bd;
      b2Body* ground = m_world->CreateBody(&bd);

      b2EdgeShape shape;

      shape.SetTwoSided(v1, v2);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v2, v3);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v3, v4);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v4, v5);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v5, v6);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v6, v7);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v7, v8);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v8, v9);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v9, v10);
      ground->CreateFixture(&shape, 0.0f);

      shape.SetTwoSided(v10, v1);
      ground->CreateFixture(&shape, 0.0f);
    }

    m_body1 = nullptr;
    m_body2 = nullptr;
    CreateBoxes();
    m_boxes = true;
  }

  void CreateBoxes()
  {
    if (m_body1)
    {
      m_world->DestroyBody(m_body1);
      m_body1 = nullptr;
    }

    if (m_body2)
    {
      m_world->DestroyBody(m_body2);
      m_body2 = nullptr;
    }

    {
      b2BodyDef bd;
      bd.type = b2_dynamicBody;
      bd.position = b2Vec2(8.0f, 2.6f) + m_offset1;
      bd.allowSleep = false;
      m_body1 = m_world->CreateBody(&bd);

      b2PolygonShape shape;
      shape.SetAsBox(0.5f, 1.0f);

      m_body1->CreateFixture(&shape, 1.0f);
    }

    {
      b2BodyDef bd;
      bd.type = b2_dynamicBody;
      bd.position = b2Vec2(8.0f, 2.6f) + m_offset2;
      bd.allowSleep = false;
      m_body2 = m_world->CreateBody(&bd);

      b2PolygonShape shape;
      shape.SetAsBox(0.5f, 1.0f);

      m_body2->CreateFixture(&shape, 1.0f);
    }
  }

  void CreateCircles()
  {
    if (m_body1)
    {
      m_world->DestroyBody(m_body1);
      m_body1 = nullptr;
    }

    if (m_body2)
    {
      m_world->DestroyBody(m_body2);
      m_body2 = nullptr;
    }

    {
      b2BodyDef bd;
      bd.type = b2_dynamicBody;
      bd.position = b2Vec2(-0.5f, 0.6f) + m_offset1;
      bd.allowSleep = false;
      m_body1 = m_world->CreateBody(&bd);

      b2CircleShape shape;
      shape.m_radius = 0.5f;

      m_body1->CreateFixture(&shape, 1.0f);
    }

    {
      b2BodyDef bd;
      bd.type = b2_dynamicBody;
      bd.position = b2Vec2(-0.5f, 0.6f) + m_offset2;
      bd.allowSleep = false;
      m_body2 = m_world->CreateBody(&bd);

      b2CircleShape shape;
      shape.m_radius = 0.5f;

      m_body2->CreateFixture(&shape, 1.0f);
    }
  }

  void UpdateUI() override
  {
    ImGui::SetNextWindowPos(ImVec2(10.0f, 100.0f));
    ImGui::SetNextWindowSize(ImVec2(200.0f, 100.0f));
    ImGui::Begin("Custom Controls", nullptr, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize);

    if (ImGui::RadioButton("Boxes", m_boxes == true))
    {
      CreateBoxes();
      m_boxes = true;
    }

    if (ImGui::RadioButton("Circles", m_boxes == false))
    {
      CreateCircles();
      m_boxes = false;
    }

    ImGui::End();
  }

  void Step(Settings& settings) override
  {
    if (glfwGetKey(g_mainWindow, GLFW_KEY_A) == GLFW_PRESS)
    {
      m_body1->ApplyForceToCenter(b2Vec2(-10.0f, 0.0f), true);
      m_body2->ApplyForceToCenter(b2Vec2(-10.0f, 0.0f), true);
    }

    if (glfwGetKey(g_mainWindow, GLFW_KEY_D) == GLFW_PRESS)
    {
      m_body1->ApplyForceToCenter(b2Vec2(10.0f, 0.0f), true);
      m_body2->ApplyForceToCenter(b2Vec2(10.0f, 0.0f), true);
    }

    Test::Step(settings);
  }

  static Test* Create()
  {
    return new EdgeTest;
  }

  b2Vec2 m_offset1, m_offset2;
  b2Body* m_body1;
  b2Body* m_body2;
  bool m_boxes;
};

static int testIndex = RegisterTest("Geometry", "Edge Test", EdgeTest::Create);
